1. Field of the Invention
This invention relates to a testing device for testing a drainage system for leaks. More particularly, this invention relates to a testing tee for testing a drainage or plumbing system for leaks.
2. Information Disclosure Statement
During the construction of a high rise building such as an office complex or a multistory residential accommodation, a plurality of drainage sections are interconnected so that sewage and the like may flow from a plurality of toilets on various floors of the building down standpipe drains to a drainage system. The standpipes are provided with test tees for testing and cleaning the drainage system. Before completion of the building, the drainage or sewage system is inspected for leaks. It is customary for the test tees in the standpipes to be opened and a plug or inflatable collar is inserted into the test tee. The drain system is then filled with water above the plug and inspected for any leakage therefrom. A conventional test tee includes an elongate tubular member which is permanently installed in the standpipe or the stack of sewage sections. The test tee includes a lateral extension and an access cover which is provided for the purpose of permitting insertion therein of the plug or inflatable collar.
A modification of the aforementioned test tee is U.S. Pat. No. 1,554,856 to Kennedy in which a plug 15 disposed within the test tee is selectively moved from a first position, in which the plug 15 engages a seat 6 of the test tee to a second position in which the plug 15 permits flow of fluid through the test tee to the drain. The plug 15 is moved from the first to the second position thereof by a mechanical linkage which is operable from the outside of the test tee.
Furthermore, U.S. Pat. No. 1,573,410 to McCabe et al discloses a test tee in which a plug 11 is selectively seated against a valve seat 8 defined by a test tee. Water is supplied to the stand pipes above the seated plug 11 through a conduit extending through the plug 11.
U.S. Pat. No. 3,941,156 to Metzger teaches a test tee having a permanently fixed plate 8 and a valve 9 for permitting drainage of the head of water above the test tee. However, the disclosure by Metzger requires removal of the head of water through hose 10 to a closet fixture 14.
However, the use of the prior art plugs involve certain inherent problems particularly when the plug was inserted into a sewage line which was not perfectly circular in cross section because the water above the plug would tend to leak past the plug thereby wrongly indicating to the building inspector the existence of a leak in the drainage system.
Because of the aforementioned problem associated with plugs for insertion within a test tee, various inflatable plugs or collars have been developed such that the inflatable plug is inserted within the test tee and connected to a source of fluid pressure to expand the flexible plug into close conformity with the internal bore of the test tee thereby avoiding the tendency of the water to leak past the plug.
U.S. Pat. No. 2,279,257 to Svirsky teaches such an expandable flexible plug 22 which is inserted within a test tee. Pressure is applied to the inside of the expandable plug 22 through a selector valve 24, which is in fluid communication with an internal cavity defined by the plug 22. Whereas the prior art inflatable plug or collar overcomes the aforementioned problems, the cost of manufacturing such a plug and the provision of a compressor for inflating the plug greatly increases the overall cost of testing drainage or plumbing installations or the like.
Also, when the inspection operation has been completed, and the prior art plug or inflatable collar is removed from the test tee and a considerable volume of water supported by the plug or collar flows downwardly through the test tee and a portion of this water flows outwardly through the cover of the test tee which sometimes causes flooding and damage to further installations at the base of the building.
The test tee of the present invention seeks to overcome the aforementioned problems associated with the prior art devices by providing a test tee with pre-installed removable disc which prevents flow of water therepast. The cover or closure of the test tee includes a hole through which the drainage system above the disc may be filled with water. Also, the present invention includes a further hole disposed below the disc such that when the test for leaks has been completed, the head of water above the disc may be directed out of the test tee through the hole in the cover and may be directed into the drain through the further hole disposed below the disc. On completion of the removal of the head of water from the drainage system, the cover or closure is removed from the test tee and the disc is removed from the test tee through the opening of the test tee. The cover is reconnected to the test tee and the test tee remains as a permanent fitting in series connection with the drainage system.
Therefore, the primary object of the present invention is the provision of a testing device or test tee which overcomes the aforementioned problems associated with the prior art testing devices and provides an improvement which significantly contributes to the ease and the low cost involved in inspecting a drainage system or the like.
Another object of the present invention is the provision of a testing device having a factory installed removable disc disposed within the test tee for selectively preventing the flow of water passed the disc.
Another object of the present invention is the provision of a testing device which permits filling the drainage system above the removable disc with water supplied to the drainage system through a hole in the cover of the test tee.
Another object of the present invention is the provision of a testing device in which the head of water above the disc is caused to bypass the disc and to flow out of the test tee through the hole in the closure and into the drain through a hole defined by the test tee and disposed beneath the disc, thereby avoiding flooding of the building on removal of the closure subsequent to testing of the drainage system.
Another object of the present invention is the provision of a testing device which is easily manufactured and which therefore costs relatively little to fabricate.
Further objects and advantages of the present invention will become apparent from the study of the following portions of this specification, the claims and the attached drawings.
The foregoing has outlined some of the more pertinent objects of the present invention. These drawings should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Particularly with regard to the use of the invention disclosed herein, this should not be construed as limited to a test tee for testing a drainage system for leaks, but should include a testing device for testing any piped installation for leaks.